FOXP4 inhibits squamous differentiation of atypical cells in cervical intraepithelial neoplasia via an ELF3‐dependent pathway

Abstract

Although the human papillomavirus (HPV) vaccine is effective for preventing cervical cancers, this vaccine does not eliminate pre‐existing infections, and alternative strategies have been warranted. Here, we report that FOXP4 is a new target molecule for differentiation therapy of cervical intraepithelial neoplasia (CIN). An immunohistochemical study showed that FOXP4 was expressed in columnar epithelial, reserve, and immature squamous cells, but not in mature squamous cells of the normal uterine cervix. In contrast with normal mature squamous cells, FOXP4 was expressed in atypical squamous cells in CIN and squamous cell carcinoma lesions. The FOXP4‐positive areas significantly increased according to the CIN stages from CIN1 to CIN3. In monolayer cultures, downregulation of FOXP4 attenuated proliferation and induced squamous differentiation in CIN1‐derived HPV 16‐positive W12 cells via an ELF3‐dependent pathway. In organotypic raft cultures, FOXP4‐downregulated W12 cells showed mature squamous phenotypes of CIN lesions. In human keratinocyte‐derived HaCaT cells, FOXP4 downregulation also induced squamous differentiation via an ELF3‐dependent pathway. These findings suggest that downregulation of FOXP4 inhibits cell proliferation and promotes the differentiation of atypical cells in CIN lesions. Based on these results, we propose that FOXP4 is a novel target molecule for nonsurgical CIN treatment that inhibits CIN progression by inducing squamous differentiation.

Androgen promotes squamous differentiation of atypical cells in cervical intraepithelial neoplasia via an ELF3‐dependent pathway

“…Paul Lambert, Tomomi Nakahara, and Iwao Kukimoto 19 . This cell line was authenticated by STR profiling and was cultured as previously reported 11 …”

“…A secondary horse‐radish peroxidase conjugated antibody was applied for 1 h at room temperature. The blots were visualized as described previously 11 …”

“…In CIN1‐derived HPV16‐positive W12 cells, the downregulation of FOXP4 attenuated cell proliferation, whereas this treatment induced squamous differentiation. This FOXP4 downregulation‐induced squamous differentiation was regulated through an ELF3‐dependent pathway, suggesting that FOXP4 is a target molecule for differentiation therapy of CIN 11 . However, the factors that regulate FOXP4 expression in W12 cells remain unclear.…”

“…We also observed the role of androgen in FOXP4 function using AR-transfected W12 cells and HaCaT cells, a human adult male skin-derived keratinocyte cell line, 16 which were reported to exhibit Ca 2+ -and FOXP4-dependent squamous differentiation. 11,17,18 2 | MATERIALS AND METHODS…”

Spheroid formation induces chemokine production in trophoblast‐derived Swan71 cells

“…RT-qPCR was performed as described previously. 22 Total RNA was extracted from Swan71 cells using the RNeasy mini kit (Qiagen, Hilden, Germany) according to the manufacturer's instructions. This RNA was reverse transcribed into cDNA using PrimeScriptTM RT-PCR Kit (Takara Bio Inc., Shiga, Japan).…”